Electrical distribution systems, for lighting and other power requirements often are comprised of surface mounted busways, to which lighting fixtures, power outlets and the like may be attached. In a typical system, the busways comprise elongated housings having a downwardly opening, generally C-shaped configuration, and containing the necessary conductors and insulation. Various output devices can be physically attached to a housing at any point along its length, and such output devices have portions which extend upward into the housing and make connections with the conductors housed therein. Such busway systems are desirable in that they are relatively easy to install and modify, and in that they provide a high degree of flexibility in the location and re-location of output devices, such as lighting fixtures and power output devices.
Busway systems frequently are installed for multiple purpose utilization. For example, for a track lighting arrangement, a number of lighting fixtures can be installed at various points on various interconnected busways, while power outlets may also be installed on the same system. Many such systems must be designed for standard voltage levels of 120-277 volts and for current carrying capacities of up to 30 amperes in order to accommodate lighting fixtures as well as a variety of other output devices. For such systems, code requirements can be rather stringent and among other things require a substantial spacing between exposed conductor surfaces and surfaces of the surrounding metal of the housing. For relatively high capacity (e.g., 30 amp) systems, operating at the standard voltages utilized (e.g., 120-277 volts), the conductors typically are recessed at the ends of a busway section, in order to assure adequate spacing between the exposed conductor ends and the adjacent housing walls. This can create problems at the jobsite, where some sections of busway, typically provided in standard lengths, may have to be cut to a shorter length for particular installation requirements. As a practical matter, job-site cutting to length while providing for recessed conductors may be impossible or impractical, and it is typical for high capacity busways of conventional design to be factory cut to custom lengths. The requirement for factory cutting of custom lengths severely impacts the flexibility of the system, where changes may be desired during installation of the system or thereafter in order to make adjustments to the distribution pattern or to accommodate structural changes.